Three-dimensional image display apparatus

Abstract

A three-dimensional image display apparatus includes a light source and an optical system including a light modulation unit having pixels for generating a two-dimensional image by modulating light from the light source by the respective pixels and emitting a spatial frequency in the generated two-dimensional image along a diffraction angle corresponding to diffraction orders generated from the respective pixels, a Fourier transform image formation unit for performing Fourier transform on the spatial frequency in the two-dimensional image to generate Fourier transform images corresponding to the diffraction orders, a Fourier transform image selection unit for selecting a Fourier transform image corresponding to a desired diffraction order among the Fourier transform images, and a conjugate image formation unit for forming a conjugate image of the selected Fourier transform image, and further includes a semi-transmissive mirror for changing a light ray travelling direction emitted from the optical system.

1. A three-dimensional image display apparatus comprising a light source and an optical system, the optical system including means for providing a plurality of pixels and generating a two-dimensional image by modulating light from the light source by the respective pixels and emitting a spatial frequency in the generated two-dimensional image along diffraction angles corresponding to a plurality of diffraction orders generated from the respective pixels, means for performing a Fourier transform on the spatial frequency in the two-dimensional image to generate a number of a Fourier transform images corresponding to the plurality of diffraction orders, means for selecting a Fourier transform image corresponding to a desired diffraction order among the number of Fourier transform images as generated corresponding to the plurality of diffraction orders, and means for forming a conjugate image of the Fourier transform image, the three-dimensional image display apparatus further comprising a semi-transmissive mirror configured to change a travelling direction of a light ray emitted from the optical system, and wherein the optical system is positioned outside a view angle of an observer. 
     
     
       2. The three-dimensional image display apparatus according to  claim 1 , wherein the light source and the optical system do not exist on an extension of a path of the light ray whose travelling direction is changed by the semi-transmissive mirror. 
     
     
       3. The three-dimensional image display apparatus according to  claim 1 , wherein an image of the light source does not exist on an extension of a path of the light ray whose travelling direction is changed by the semi-transmissive mirror. 
     
     
       4. A three-dimensional image display apparatus comprising a light source and an optical system, the optical system including light modulation means provided with a plurality of pixels and configured to generate a two-dimensional image by modulating light from the light source by the respective pixels and to emit a spatial frequency in the generated two-dimensional image along diffraction angles corresponding to a plurality of diffraction orders generated from the respective pixels, Fourier transform image formation means configured to perform Fourier transform on the spatial frequency in the two-dimensional image emitted from the light modulation means to generate a number of a Fourier transform images corresponding to the plurality of diffraction orders, Fourier transform image selection means configured to select a Fourier transform image corresponding to a desired diffraction order among the number of Fourier transform images as generated corresponding to the plurality of diffraction orders, and conjugate image formation means configured to form a conjugate image of the Fourier transform image selected by the Fourier transform image selection means, the three-dimensional image display apparatus further comprising light ray control means configured to change the travelling direction of the light ray emitted from the optical system and control a collecting state of the light ray emitted from the optical system at an observation spot and wherein the light modulation means, the Fourier transform image formation means, the Fourier transform image selection means, and the conjugate image formation means are positioned outside a view angle of an observer. 
     
     
       5. The three-dimensional image display apparatus according to  claim 4  wherein the light ray control means is composed of a concave mirror. 
     
     
       6. The three-dimensional image display apparatus according to  claim 4  wherein the light ray control means is composed of a lens which the light ray emitted from the optical system enters and a minor which a light ray emitted from the lens enters. 
     
     
       7. The three-dimensional image display apparatus according to  claim 4 ,
 wherein the light ray control means is composed of a mirror, 
 wherein the light ray control means further includes detection means configured to detect the observation spot, and 
 wherein the light ray control means controls a position of the mirror on the basis of a detection result on the observation spot by the detection means. 
 
     
     
       8. The three-dimensional image display apparatus according to  claim 4 ,
 wherein the light ray control means is composed of a lens which the light ray emitted from the optical system enters and a mirror which a light ray emitted from the lens enters, 
 wherein the light ray control means the light ray control means further includes detection means configured to detect the observation spot, and 
 wherein the light ray control means controls a collecting state of the lens on the basis of a detection result on the observation spot by the detection means. 
 
     
     
       9. A three-dimensional image display apparatus comprising a light source and an optical system,
 the optical system including 
 a light modulation unit provided with a plurality of pixels and configured to generate a two-dimensional image by modulating light from the light source by the respective pixels and to emit a spatial frequency in the generated two-dimensional image along diffraction angles corresponding to a plurality of diffraction orders generated from the respective pixels, 
 a Fourier transform image formation unit configured to perform Fourier transform on the spatial frequency in the two-dimensional image emitted from the light modulation unit to generate a number of a Fourier transform images corresponding to the plurality of diffraction orders, 
 a Fourier transform image selection unit configured to select a Fourier transform image corresponding to a desired diffraction order among the number of Fourier transform images as generated corresponding to the plurality of diffraction orders, and 
 a conjugate image formation unit configured to form a conjugate image of the Fourier transform image selected by the Fourier transform image selection unit, and 
 the three-dimensional image display apparatus further comprising a semi-transmissive mirror configured to change a travelling direction of a light ray emitted from the optical system, and 
 wherein the light modulation unit, the Fourier transform image formation unit, the Fourier transform image selection unit, and the conjugate image formation unit are positioned outside a view angle of an observer. 
 
     
     
       10. The three-dimensional image display apparatus according to  claim 1 , wherein the semi-transmissive mirror includes a dielectric multilayer film. 
     
     
       11. The three-dimensional image display apparatus according to  claim 1 , wherein the semi-transmissive mirror changes a traveling direction of the conjugate image formed by the conjugate image formation means.